I’m not sure if it’s been mentioned elsewhere, but it would be very useful to be able to change which race you’re using on the deployment screen of a challenge. Currently it’s a bit long-winded to get to.
I second this. Having a “change race” button below the save/load ones could work.
I third this. It’s a good idea. It would also be nice if the ship designer, when accessed from the deployment screen, only showed hulls from the race you have selected. The main menu ship designer could be preceded by the race selection screen, so that only one ship designer implementation is required.
Yeah, the new Hull selector is great, but it can be a bit of a pain selecting a single hull from one big list (or am I just being demanding?). The race selector could indeed could be accessible directly from the design menu, or be a simple 4-way radio button in the hull selector list.
I’d settle with actually making custom races selectable.(cmon cliff) 
I think the hull selector should be pretty high in the priority list for a makeover. It needs filtering by class and race, as well as sorting by hull type, cost, class?, speed, damage, armor, etc…